1. Field of the Invention
The present invention relates to biopsy forceps and, more particularly, relates to an endoscopic biopsy forceps device incorporating a novel and unique camming arrangement for selectively opening and closing the biopsy cutting jaws of the biopsy forceps which will render the entire device of a simpler construction and reliable in operation, while concurrently marking it considerably less expensive to produce.
Although varied types of biopsy forceps are currently in widespread use, such as in conjunction with endoscopic purposes, these are generally of complicated constructions necessitating the manufacture and assembly of numerous, highly precise components and, as a consequence, are quite expensive. Ordinarily, an endoscopic biopsy forceps device must be sterilized in strict compliance with rigid medial standards after each use thereof with a patient, so as to enable the device to again be safely employed with another patient for subsequent medical and/or surgical endoscopic biopsy procedures. Such sterilizing procedures entail immersing and rinsing the contaminated endoscopic biopsy forceps devices in a suitable chemical sterilizing solutions and/or subjecting the biopsy devices to sterilizing in an autoclave. The sterilizing of the biopsy devices with the utilization of chemical sterilizing solutions has, in more recent years, given rise to concerns that the contaminated biopsy devices were not adequately sterilized for reuse with other patients, particularly in view of the considerable dangers to patients through exposure to potentially serious and even life-threatening infection with the AIDS virus (Acquired Immunity Deficiency Syndrome) or hepatitis B viruses, wherein sterilizing of the devices by means of such chemical solutions may not always be adequate to destroy the viruses, or at the very least, raise doubts as to the efficacy of the solutions. Furthermore, subjecting currently utilized endoscopic biopsy forceps devices to sterilizing procedures in an autoclave, under extremely rigorous physical conditions, frequently causes the rather delicate biopsy forceps devices to be destroyed, or damaged and warped to such an extent as to render the devices unusable for repeated applications.
In order to overcome the limitations and drawbacks which are currently encountered in the technology, and particular in endoscopy, with respect to the constructions and employment of endoscopic biopsy forceps which will meet with the requirements of the medical profession, the present invention contemplates the provision of an endoscopic biopsy forceps device which, to an appreciable and highly desirably extent, reduces the large number of components in each such device; and in particular, affords for a considerable reduction in the necessary articulated elements, pivot points, rivets and attendant riveting operations in assembling the forceps device. In view of the complex construction of such prior art biopsy forceps devices are extremely expensive, and because it may not always be possible to properly sterilize the device to provide adequate safeguards against infections for patients exposed to previously used devices, rendering discarding thereof uneconomical, and possibly subjecting the medical facility and/or staff to legal liabilities in the event a patient is infected by a contaminated device.
2. Discussion of the Prior Art
Among the typical types of endoscopic biopsy forceps and similar types of devices which are currently known, the following are considered to be representative of the state-of-the-technology.
Komiya U.S. Pat. No. 4,038,987 discloses a forceps device for an endoscope, wherein the operation of the cutting jaws of the forceps are effectuated through the intermediary of a toggle joint which is articulated by a control wire through the interposition of suitable linkage components. The toggle mechanism provided for in this patent necessitates the utilization of separate pivot pins for each forceps jaw and provides for the type of operation in which the least amount of mechanical advantage is applied to the jaws during the closing of the forceps. This structure utilizes a multiplicity of linkage elements and pivots, rendering it highly susceptible to damage during sterilizing, while the device is extremely expensive because of the numerous components employed therein, necessitating the repeated use thereof in order to cause the device to be economical.
Blake, III, U.S. Pat. No. 4,662,374 discloses a ligator device in which a cam track is employed as a so-called "time delay" for the retraction of the clips proximate one of the clamping jaws. The operation of the camming arrangement utilized in Blake is completely unlike that of the camming arrangement utilized in the inventive endoscopic biopsy forceps and, moreover, necessitates the incorporation of an additional toggle mechanism in order to actuate the movement of the jaws. This particular device would not be employable as an endoscopic biopsy forceps.
Rich U.S. Pat. No. 4,572,185 employs a movable pin engaging a cam track in an operative mode as described hereinabove with respect to Blake, and necessitates the incorporation of a secondary pin as a pivot for the jaws of a surgical needle holder. This structure requires a more complex pin and cam track arrangement in comparison with the inventive endoscopic biopsy forceps device, and necessitates the utilization of auxiliary components which render the structure thereof expensive and inapplicable to a simple biopsy forceps device as is contemplated by the present invention.
Walter, et al. U.S. Pat. No. 4,171,701 primarily pertains to a camming structure incorporated into a tweezer device, which requires the use of secondary pin and linkage components in order to actuate the jaws of the device, and is not at all suggestive of the simple, reliable and inexpensive camming arrangement employed in conjunction with the inventive endoscopic biopsy forceps device.
Further types of biopsy forceps and the like, all of which employ relatively complex pivot points, linkages and toggle mechanisms, are respectively disclosed in Komiya U.S. Pat. No. 3,840,003; Hayashi U.S. Pat. No. 4,669,471; Maslamka U.S. Pat. No. 4,646,751; and Schmidt U.S. Pat. No. 3,895,636. The constructions disclosed therein are primarily of the complex pivot pin and linkage systems, also employing toggle linkages and parallelogram linkages, which render the devices extremely complex, expensive and not at all adapted for single use or so-called throw-away operation as contemplated by the invention.